58Mathematically, pH is the measurement of hydroxyl ion activity and expressed as the negative
logarithm of the activity of the (solvated) hydronium ion, more often expressed as the measure of
the hydronium ion concentration.
Contents
History
The scientific discovery of the p[H] concept of was first introduced by Danish chemist Søren Peder
Lauritz Sørensen at the Carlsberg Laboratory back in 1909 and revised to the modern pH in 1924
to accommodate definitions and measurements in terms of electrochemical cells. In the first papers,
the notation had the "H" as a subscript to the lowercase "p", as so: pH.
Alkalinity
Alkalinity is the quantitative capacity of an aqueous solution to neutralize an acid. Measuring
alkalinity is important in determining a stream's ability to neutralize acidic pollution from rainfall or
wastewater. It is one of the best measures of the sensitivity of the stream to acid inputs. There can
be long-term changes in the alkalinity of rivers and streams in response to human disturbances.
Reference. Bates, Roger G. Determination of pH: theory and practice. Wiley, 1973.